The present invention relates to a thin film magnetic slider for realizing high-recording density of a magnetic disk drive, a magnetic head support mechanism, a magnetic disk drive, and a method for manufacturing a magnetic head. In particular, the invention relates to a flying height adjusting slider having a function of adjusting a distance between a magnetic disk and a magnetic head.
A known disk storage unit has a magnetic disk to be rotated and a thin film magnetic head slider (hereinafter referred to as “slider”) which is positioned in a radial direction of the magnetic disk. The slider has a recording/reproducing device and is supported by a magnetic head support mechanism having a suspension. The slider runs relatively above the magnetic disk to read and write magnetic information from and to the magnetic disk. The slider serves as an air lubricant bearing and flies owing to a wedge film effect of air, so that the magnetic disk and the slider are not brought into a direct solid contact with each other. In order to realize the high recording density of the disk storage unit and resulting larger capacity or downsizing of the storage unit, it is desirable to increase a linear recording density by reducing a distance between the slider and the magnetic disk, i.e., the slider flying height.
Conventionally, in designing the slider flying height, a flying height margin has been provided in view of a variation in processing, an air pressure difference depending on use environment, a temperature difference depending on use environment, and the like in order to prevent the contact of the slider with the disk even under the worst conditions. If a slider that has a function of adjusting a flying height for each head or for each use environment is realized, the above margin can be eliminated. Consequently, a flying height of the write/read device is largely reduced while the slider can be prevented from coming into contact with the disk. For example, in a known slider structure, a heating device comprising a thin film resistor is provided in the vicinity of write and read devices, and a part of a slider is heated as required to thermally expand and protrude, thereby adjusting a distance between the write and read devices and a magnetic recording medium (see, for example, Japanese Patent Laid-open No. 5-20635 (page 3 and FIG. 1)).
Conventional sliders are provided with read relay terminals for electrically connecting a magnetic read device to the external and write device terminals for electrically connecting a magnetic write device to the external. One of the sliders requires, in addition to the read device terminals (two terminals) and the write device terminals (two terminals), a pole corrosion prevention terminal (one terminal) for suppressing corrosion of a magnetic film in a solution during polishing and cleaning processes of a production process (see, for example, Japanese Patent Laid-open No. 2003-77105 (page 3 and FIG. 1)). The number of terminals in the slider requiring the pole corrosion prevention terminal is five in total.
With the installation of another terminal for a heating device which energizes and heats for the purpose of flying height adjustment, a problem of difficult mounting has been detected. The conventional slider has five terminals in total, namely, the write device terminals, the read device terminals, and the pole corrosion prevention terminal. In the case of adding the terminals for a microthermal actuator used in the heating device for the flying height adjustment, the number of terminals is increased to seven, thereby making it difficult to mount them. Because a next generation slider to which a thermal flying height adjustment slider of the present invention is applied will be further downsized, it will be even more difficult to mount seven terminals on the slider.
Further, in the case where the seven terminals are mounted on the slider, a region on which the pole corrosion prevention terminal is mounted is inevitably assigned to a position near the air bearing surface.
The known slider production process includes a polishing process for shaping the air bearing surface and a cleaning process for eliminating process residue. In this case, a protection material which is provided near the terminal is scraped off due to the polishing process, thereby undesirably exposing the pole corrosion prevention terminal. Since a brush used in the cleaning process for eliminating processing residue can often be charged, there is a risk that the pole corrosion prevention terminal is undesirably eroded due to charging at the time of contact with the brush.